Measuring Welder Output

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So--I've got a Lincoln PowerMIG 200.  I'm very happy with it, and as I'm using it at home for light to medium fab work I doubt I'll ever outgrow it (at least without upgrading my electrical service anyway).The 200 is a tapped transformer machine as opposed to an infinitely adjustable machine like the 255.  So far I've just been using the recommended settings inside the cover of the machine and they seem to be working fine.I'm not completely confident of my understanding of the electronics being welding.  Can someone give me a brief rundown of the differences in a tapped transformer machine and a machine with infinitely adjustable power?  What exactly am I changing when I switch taps on my welder?  Amperage?  Voltage?  Both?  Neither?And finally, I've got a 400A/600V Fluke Inductive Amp pickup.  Could I just clamp it over the welding cable (or possibly the wire inside the cover), start welding, and have someone read the meter, allowing me to "label" the different taps to have some idea where they fall in output?  Could I do the same with voltage?  If nothing else I think it would be somewhat interesting to see the difference in the readings as I vary the amount of stickout.  Would my readings have any sort of consistency, or is the output of the machine going to vary depending on different weld parameters?  If so, which?Thanks in advance.
Reply:Start here with tapped.  Set the machine by the chart and then turn the wire feed as you are running to the most consistant arc.  The feed speed is the amount of power adjustment.  If you want more power than that range then turn the V up a notch and turn the feed up to match.  With a vairable you could tune the V or arc intensity to match the wire speed instead of the other way around. When you change taps you are changing voltage.  When you change wire speed you are changing amperage.  Follw the chart for the tap and tune with the wire speed.  Its as simple as that. I never meter mine,, I dont need to, to me its useless to know what the numbers mean, I want it to weld right.  I adjust it for the best arc.www.urkafarms.com
Reply:Jon;First if your fluke clamp on is an inductive meter, it's strickly an AC meter. The welder output is DC.S is right when you change taps basically you're changing voltage. The "taps" are connections inserted in the secondary winding of the transformer. Following "Ohms law" when you change voltage you'll change amps also, but the major amp variable is the wire speed. I recommend buying the Miller student package it has a very good electricity for wekldors book. the MIG book is worth the 25 bucks alone.For most of us measuring voltage and amps is a waste of time. If you follow the chart on the door and modify your settings from there you'll do fine.Last edited by fla jim; 03-23-2004 at 07:25 AM.
Reply:Some of us just have a need to know.   I have a Fluke ac/dc clamp on that you plug a dvm into. I just hook it around the dc power lead for current. One millivolt equals one amp. To measure the output voltage, just hook your dvm to the dc leads.
Reply:Thanks for the replies guys.  My Fluke clamp IS AC/DC (I went out and checked).I ordered the Miller Student package--looks like a really good deal.The reason I made this post is because I wasn't really sure I'd be getting any meaningful information out of sticking a meter on the welder.  Based on the replies it seems like everyone feels that a consistent arc is a lot more important than a bunch of numbers on a dial somewhere.  You'd think I would have figured this out by now given the number of experiences I've had with people that put more stock in a specific number than real world results.  It's sinking in slowly.I still may drag my wife out to the garage to play around with the meter though.  What can I say, I'm a curious mofo.A couple more questions:How does adjusting the wire feed speed control the amperage draw?  I assume by changing the frequency of short circuits?  Therefore a higher wire speed feed would draw more amps, correct?  Do more amps = more penetration?  It seems to me that what I'm really trying to do is optimize the amperage draw with the wire speed for my specific welding situation, and that there's a "sweet spot" where I'll get optimum penetration, but too slow or too fast and I'll loose effectiveness.  Am I on the right track here?  I know about tuning the welder by sound but I'm new to welding so I'm not fully comfortable with my ability to do so.And also, I read somewhere about tapped transformer designs being suitable for use on generators whereas the infinitely adjustable welders weren't?  Is this true?  Why?
Reply:Jon, you hit the nail square on when you ssaid performence means more than a bunch of numbers.Once you've got the technique down, you won't look at the numbers for more than a place to start, and your ears will tell you when the arc is running right..As far as running SCR type machines from generators, if the genset is sufficiently sized, it isn't a problem, unless the genset is not frequency stable.Appreciation Gains You Recognition-
Reply:JonB, your numbers do have an importance. Consider this, there is a certain setting on my machine that makes the absolute sweetest sounding short circuiting sound, but the amount of weld energy made is good for joining 16ga type sheet metal. That same setting will not properly fuse 1/4" thick material-true the arc will sound oh so sweet..to bad the part is likely fail.Curious how with SMAW it is ok to think that different rod sizes are matched to different metal thickness and differing amp requirments. Yet with mig  numbers lose their importance.Arc sounds will aid you in tuning the arc, but the numbers will help you from becoming another glue gun welder. You can hear this for yourself, set your machine on D or E w/wirespeed around 210. .. Now, set to G, set whatever you like with the wirespeed and try to match the previous arc sound...."after a long day of doing nothing...its gooood to kick back" Pumbaa
Reply:When we test for certain companies the inspector will take a reading of amps and voltage on every pass. Sometimes in the field they will do the same thing as a spot check. They are documenting that you are within the procedure, the welding procedure will have a range of amps/volts that are acceptable. They just clamp around the stinger lead to read amps, and put a multi meter on the welding lead lugs to read voltage. This is CC of course, and may or may not have any relevance to what you want too do. But then it might.regards,JTMcC.
Reply:PlanetX, you misunderstood me.  I wasn't implying that tuning by sound was the end all/be all of adjusting a welder, I was trying to say that the end result (quality of the weld) was more important than an actual number on a dial somewhere.  I'm still a newbie at welding and I'm not trying to pass myself off as an expert or anything so I'm sorry if I offended you.I received my Miller Student Package today.  fla jim, thanks for the recommendation.  I have a much better understanding of the amperage/wire speed relationship and voltage adjustment now.I went out to the garage tonight with my watch, tape measure, DVM and amperage probe.  I found out a couple of things:- The numbers on the Wire Speed dial on my welder are pretty close to the actual IPM.  At 300 on the dial it put out 29.5" of wire in 6 seconds.  (I tested it in a couple other positions as well and it was close)- At the recommended setting for .135" steel (tap "D" and about 240IPM wire speed), I measured 150 amps and 19.5 volts.  I'm using 75/25 mix and .035 wire.  This seems more or less in-line with the numbers that my "Millermatic Calculator" that came with my Miller Student package would recommend (it says 140-150 amps, 18-19 volts for .125" metal)I didn't get a chance to try any other settings because I somehow managed to dip my gun into the puddle and weld the end of my contact tip up completely solid.  (No, I have absolutely no idea how I managed to do something that stupid).It was actually *really* informative to see the difference in amperage output as I adjusted the wire speed, or changed the amount of stickout.
Reply:JonB, communicating through writing is not a strength of mine My main point was that metals of different thickness and differing joint types would require different amperage levels to be put into the weld to avoid the 'mig molten glue gun stigma'.And Short circuit welding gets its sound from the # of on/off arcs per second. And the maximum short circuits with a given diameter of wire per second, may sound like the ideal 'frying bacon' it may not necessarily be drawing the right amount of amps from the machine for the part being welded. To ensure proper weld fusion.For example on my Powermig right around 17volts & 210-230 I get the 'max crispy', but this does not put out enough amps to ensure proper fusion with say .120wall thick steel.  Oh it will generally stick together well enough, but sometimes what I am welding needs to stay welded. Sometimes its no big deal, all depends on the part I'm building or welding.Arc sounds and #'s have their place especially if you are self-learning oh, I'm a newbie too- I just post a lot"after a long day of doing nothing...its gooood to kick back" Pumbaa
Reply:Originally posted by JonB PlanetX, you misunderstood me.  I wasn't implying that tuning by sound was the end all/be all of adjusting a welder, I was trying to say that the end result (quality of the weld) was more important than an actual number on a dial somewhere.  I'm still a newbie at welding and I'm not trying to pass myself off as an expert or anything so I'm sorry if I offended you.I received my Miller Student Package today.  fla jim, thanks for the recommendation.  I have a much better understanding of the amperage/wire speed relationship and voltage adjustment now.I went out to the garage tonight with my watch, tape measure, DVM and amperage probe.  I found out a couple of things:- The numbers on the Wire Speed dial on my welder are pretty close to the actual IPM.  At 300 on the dial it put out 29.5" of wire in 6 seconds.  (I tested it in a couple other positions as well and it was close)- At the recommended setting for .135" steel (tap "D" and about 240IPM wire speed), I measured 150 amps and 19.5 volts.  I'm using 75/25 mix and .035 wire.  This seems more or less in-line with the numbers that my "Millermatic Calculator" that came with my Miller Student package would recommend (it says 140-150 amps, 18-19 volts for .125" metal)I didn't get a chance to try any other settings because I somehow managed to dip my gun into the puddle and weld the end of my contact tip up completely solid.  (No, I have absolutely no idea how I managed to do something that stupid).It was actually *really* informative to see the difference in amperage output as I adjusted the wire speed, or changed the amount of stickout.
Reply:Originally posted by Dan JonDid you have someone reading your meter for you, or were you using a peak hold feature?
Reply:Hmmmn.........with .035 wire and CO2, I run at 26 volts and 100 amps. Very little splatter. We need some charts of wire size and amps.